Stinkhorns are amazing mushrooms, notorious for popping up suddenly and unexpectedly in urban settings. They are very diverse in appearance, but all of them share at least two features:

Some part of the fruiting body, at some stage in development, is covered with a foul-smelling slime.

The fruiting body arises from an "egg," traces of which may disappear by maturity.

Beyond these shared features, however, just about anything goes, and stinkhorns range from looking rather like morels to appearing like, um, a portion of canine anatomy, or odd marine creatures with tentacles, or crab claws, Wiffle balls, Chinese lanterns, and so on.

Stinkhorns occur "naturally" in North America, especially in subtropical and tropical regions--but some stinkhorn fruitings in temperate and north-temperate climates may be caused by human endeavors, resulting from the transportation of soil, sod, wood chips, trees, and so on. Thus Lysurus mokusin appears outside a library in Lawrence, Kansas, and Aseröe rubra shows up in gardens in South Carolina.

The method the stinkhorns use to disperse spores is quite ingenious, though a little disgusting to human sensibilities. The foul-smelling slime is calculated to attract flies and other insects, who land on the slime and gobble it up. Little do the insects know that they have been duped into covering their little insect feet with stinkhorn spores, and have ingested spores into their digestive tracts! Later, these spores are dispersed by the unwitting insects, and the stinkhorn life-cycle continues elsewhere.

One stinkhorn, Phallus impudicus, is often mistaken for a yellow morel by summer morel hunters who are hunting with their hearts instead of their minds. However, the season alone (to say nothing of the presence of stinky slime and the underground "egg") should serve to separate the stinkhorn; morels don't grow in summer . . . and "de Nile" is not just a river in Egypt.

I doubt that any mushrooms, with the possible exception of Leucocoprinus birnbaumii (which pops up out of nowhere in people's flower pots), generate more "What's This Mushroom?" e-mails than the stinkhorns. They are truly astonishing when they grow literally overnight in your yard or garden. So, to anticipate a few questions in advance: No, they won't hurt you (or your children, or your pets); No, I will not tell you how to get rid of them (it's pretty much impossible, but even if they were easily eradicated, why would a mushroom lover tell people how to kill mushrooms?); and Yes, I would love to see your photos (my e-mail address is on this page).

Traditionally, two families of stinkhorns were recognized. The Phallaceae held stinkhorns with unbranched stems, including species of Mutinus, Phallus, and Dictyophora (now synonymized with Phallus), among others. The Clathraceae included stinkhorns with branched stems and those with funky, latticed structures--including Clathrus, Lysurus, Colus, Laternea, and others. Although the current Dictionary of the Fungi contradicts itself on the status of these two stinkhorn families (the entry for the order Phallales includes the Phallaceae but not the Clathraceae, while the entry for the Clathraceae indicates it belongs in the Phallales) it is rather a moot point, since recent DNA research has indicated that the order Phallales also includes many coral mushrooms, species of Gomphus like Gomphus floccosus, and earthstars like Geastrum saccatum. See the page for the Phallales for further information.

With a more or less central, single (not composite) stem that is clearly visible above the volva for at least a few centimeters; the stem may then split into columns or tentacles (which may or may not rejoin at the very top), or it may support a latticed structure.

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Central stem if present composite, composed of multiple arms fused together--or stem absent or rudimentary, not extending more than a centimeter above the volva.

Stem holding aloft a pointed structure that lacks prominent cross-lattices--or stem branching into vertical arms, appearing like claws or tentacles, that may fold back by maturity.

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15.

Stem holding aloft a pointed structure with 4-6 short columns (under 4 cm long) that are firmly fused at their tips at first but may separate slightly at maturity.

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15.

Stem terminating with 3-22 long arms (longer than 4 cm) that may or may not be joined at their tips initially, but by maturity may be separated and spread out like octopus or squid tentacles.

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Claws covered with spore slime all the way to their bases, almost always separating and folding back somewhat by maturity; reported from Ohio and Kansas, and to be expected throughout subtropical and tropical North America.

Arms numbering 3-4, usually remaining fused at their tips or peeling back only slightly by maturity; documented from northeastern North America and Kansas, to be expected across the continent; spores 3.5-4.5 x 1.5-2 µ.

Stinkhorn consisting of a cage-like structure, with horizontal cross-lattices (at least near the top of the structure) in addition to vertical lattices.

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19.

Stinkhorn without horizontal cross-lattices, consisting only of vertical columns which may or may not be fused at their tips--and which may or may not peel back at maturity to appear like the arms of an octopus or squid.

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20.

Cross-lattices numerous, but only occurring at the top of the stinkhorn, held aloft by 4-6 vertical columns which are often fused together into a stemlike structure; reported from Jamaica.

Spore slime confined to the upper portion of the interior surfaces of the columns (rarely lower than the top half).

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28.

Spore slime covering the entire interior surfaces of the columns, from top to bottom.

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29.

Stinkhorn with 2-5 columns up to 15 cm tall; reddish to orangish; occasionally with a cross-lattice or two; distributed from New York to the Gulf States, Illinois, and Mexico; especially common in Florida.